Running Issues at Cold

Funkyfin2000 said:
Yeah need to get a new one - how did you get on this morning mate?
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Well after parking up the car last night at 8pm, I went to start it about 45 mins ago.

The new battery in the car was only showing 21.39v (which seems too low for a new battery left for less than 24 hours?) , and the old one in the boot was still showing 12.60v over the same period.

With both of them linked in parallel, the car did start quicker, although still not as fast as normal, and the brake warning like still came on.

It was also a mild 11.5 degrees tonight which probably helped. But I'll try linking the batteries up again tomorrow morning, except this time with my backup battery 'fresh' straight off the charger and see what happens.
 
If you could get hold of a "clamp meter" then you could see how much currant the starter draws when cold, also would show if there was any drain with everything off!
 
I can measure current draw with my multimeter, although I'd have to just tape the test probes to the terminal and battery clamp so they had constant contact.

What's the process for measuring the current draw when the car is fully off. Like do I need to lock the car with the bonnet open, or leave it a certain amount of time etc.?
 
I'd say if you crack this you'll crack it for a lot of people.

Talking about charge, leaving the ignition on for 25secs or so tends to help more as well with my issue. Did it this morning (granted not as cold as you mention) and it certainly wasn't as lumpy for as long as normal.

I think your issue appears acutely worse, I only sometimes have it bad enough to get the brake warning light...and only normally when it's more colder.

Why would the issue be worse in winter when cold if it's a charge issue.

Can any recommend a multimeter off eBay? I'm a bit rubbish with electrical things!

Cheers all

Rich
 
To test currant draw with everything off you need to connect your amp meter between the battery neg terminal & the earth lead. Do not crank your engine like this or you will fry your meter, that's why you need something heavy duty like the clamp meter. You need to close the bonnet with the meter outside or on the dash if the leads are long enough. Lock the car & wait for everything to close down, then see what the amp reading is!
 
If it is battery drain, that still leaves the hard part of actually finding what's draining it, not looking forward to that!

The slow starting has been happening since the cold weather came but the brake warning light has only been illuminating during 'cold cranking' since Boxing Day, which was right after a period of roughly a day and a half when the car didn't move. But I only get the slow start and warning light on the first start of the day.

I guess because the oil and possibly the fuel thicken slightly when it's colder, it shows up any weakness in the battery more. Also because the power in a battery is not stored as such, it's created by a chemical reaction, and like most chemical reactions it slows down when it's cold.
 
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Yes if you do see a drain with everything off, you need to start pulling fuses until you find the circuit showing a drain!
 
Also on the subject of multimeters, I personally have a Limit 300 which can test AC/DC for volts, current draw, resistance, continuity and also temperature.

I got that particular model because I got a decent price as my work stocks them. Seems pretty well spec'd, and they go for under £30 on eBay.
 
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Yeah very similar to me then....I've had mine for years now and in summer it's fine, come the cold weather then it starts.

Clearly I've done a lot of work to try and sort but none of it has made any difference. The audi will be parked up more now as just took delivery of a Golf R so will see if worse when left. As you say through the day its find, just when left for a longer period of time.

When you rev it even lumpy it really is very lumpy! Then just solves itself! :)
 
john777w said:
Yes if you do see a drain with everything off, you need to start pulling fuses until you find the circuit showing a drain!
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Do I really need to have the bonnet shut for it to go into 'fully off' mode? That's going to make seeing the screen and pulling fuses great fun if it needs to be shut and left every time!
 
I guess it will show the bonnet as open & alarm might not set, not certain on this, as never had to try it on an Audi.
 
john777w said:
I guess it will show the bonnet as open & alarm might not set, not certain on this, as never had to try it on an Audi.
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When I locked it with the bonnet open last night, the red blinking light still came on. But the indicators didn't flash when I pressed the button...
 
So today, I Put the key in the ignition, waited two secs for the glow plug light to go out and cranked. Brake warning and lumpy. So defo, if I leave the key in for 20-25 secs it's a lot better.

It's like piecing the information together. I think you are on the right track though, battery drain may well be the issue here.

I might get a new battery for it, any ideas on recommendations? Ampage etc??
 
I'd replace the heater plugs mate
And have you thought about a battery jacket ? I had them on older cars like mk3 golfs etc

I don't know if it actually makes a difference but surely they were there for a reason, too keep the battery temp stable
 
Funkyfin2000 said:
Researching I found this - will check hazard switch, but is it worth pulling the alternator wires and see if this helps starts?

http://forums.tdiclub.com/showthread.php?t=244419
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My hazard light switch only stays on for approx 30 seconds after the car is locked, then goes out.

I'll try putting my phone on video mode and putting it in the glove box and boot to make sure the lights are going out though.
 
audi upgrades
You can see the boot light looking down through the glass....

I'm going to check my hazard switch now.....

Will also check glovebox light now as well.....

In terms of the wire to the alternator from the battery - I see a big think red cable that goes towards the ECU and to the left hand side of the bay - but there is also a wire that goes right under a scuttle tray...
 
Just saw this on a post too -

FYI All the "Brake!" warning is a common fault on the TDI for starting in cold weather and is NOT an indication of a battery that is due to fail!!

I've just been talking to an Audi tech and apparently the higher current required to warm up the glow plugs in cold weather caused the brake warning sensor to trigger a false alert - he said it's very common on TDI's - in particular the V6's. It is often associated with a "failing" battery as the car usually puts a lot more strain on the battery when starting in colder temperatures, so you can get the battery warning just before a failed crank and then if the car fails to start again after that, people blame the "Brake!" warning as the main symptom they saw before the battery gave up. By itself, it is NOT an indication the battery is about to die, if anything, the opposite!

Audi are able to fix it (for free, I assume), but the guy said they just put a little relay that stops the brake failure sensor from working for the first few seconds until the (until the current to the glow plugs has dropped) - don't think I'll bother getting mine done, but good to know now that I should take that as a sign of a healthy battery that's just warming up the glow plugs nice and fast, albeit from a sub-zero temp :)
 
Funkyfin2000 said:
You can see the boot light looking down through the glass....

I'm going to check my hazard switch now.....

Will also check glovebox light now as well.....

In terms of the wire to the alternator from the battery - I see a big think red cable that goes towards the ECU and to the left hand side of the bay - but there is also a wire that goes right under a scuttle tray...
Click to expand...

The smaller wire to the alternator should be the wire back to the dash warning light!
 
Funkyfin2000 said:
So Sprinter (whats ya name!) I'm going to unplug the battery negative altogether tonight and leave it off.....then reconnect and try starting in the morning...
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My real name is David, although I am actually a sprinter as well (as in the athlete kind, not the Mercedes van)

Can leaving it unplugged long term cause any issues with forgotten settings or keys nit being recognised etc?
 
Funkyfin2000 said:
Unplugged now......plugged in and alarm went off and keys lost remote central locking but I can redo that easily tomorrow.....

So will test and see how we get on...
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Yer mine lost the keys too, but both the radio and keys (once they've been in the ignition) should reprogramme themselves without any codes etc.

I tried starting with my backup battery again tonight, hooked it up with jump leads again. 21.49V showing on the battery in the car, but 13V showing with both batteries hooked up.

Still didn't appear to make any difference to how quickly it started, so although my battery does appear to be losing a small amount of charge overnight, that doesn't seem to be the cause of the slow starting.

It did however blow a tail light bulb while idling after I started it which was weird. Coincidence or electrical surge from having both batteries hooked up?
 
I don't get this 21.49v you would only see that if they were wired in series, in parallel you should only be seeing 13+ volts, if you were putting that voltage through the system you would fry the electrics??
 
audi upgrades
john777w said:
I don't get this 21.49v you would only see that if they were wired in series, in parallel you should only be seeing 13+ volts, if you were putting that voltage through the system you would fry the electrics??
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Oops, that was meant to say 12.49V. Don't worry I haven't been wiring up my batteries in 24V configuration!
 
Interesting, so maybe the battery drain is a red herring...

I havn't got a multimeter so my test is purely about seeing is the battery drain is a red herring or not I guess. If I hook it up tomorrow and find it all OK once plugged in then it can't be a drain issue surely?
 
Funkyfin2000 said:
Interesting, so maybe the battery drain is a red herring...

I havn't got a multimeter so my test is purely about seeing is the battery drain is a red herring or not I guess. If I hook it up tomorrow and find it all OK once plugged in then it can't be a drain issue surely?
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So, not a great morning, plugged the battery back in, waited 2 secs and glow plug out, no brake warning but still pretty rough running for 5 secs or do, albeit not for quite as long...sigh I dunno :-(
 
Still waiting to hear back from the garage about when they can change my thermostat and temp sensor.

Also going to get them to change the glow plugs while they're at it. Once that's done and I can cross them off the list I'll do some more fault finding.

On a plus side it's been starting much easier this week, although it's still a bit lumpy at idle / stalls easily for the first minute or so.
 
Not from me, still waiting for my garage to pull their finger out! lol Bit of a pain for them to be fair because the work is being done as part of a 3rd party warranty claim so they have do get approval etc.
 
Did you sort this out, im having very similar issues...injectors seals and camshaft left to do.
 
audi upgrades
bet its something simple thats overlooked. i hate it when things arent right.
 
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